Quck answer
Wiring an electric water heater involves several steps. First, turn off the power and drain the water tank. Then, remove the access panel and connect the wires to the thermostat and heating elements. Make sure to follow the manufacturer’s instructions and use the correct gauge of wire. After wiring, turn on the power and test the heater for proper functioning. It is important to take necessary safety precautions and consult a professional if unsure.
Electric water heaters can last up to 15 years, but if you plan on staying in your home longer, you may need to replace it. This involves hooking up the wiring, which is also necessary if you switch from a gas to an electric water heater. For high-demand appliances like these, which run on 240 volts, homeowners should avoid electrical work, especially in the electrical panel. However, understanding the process can give you an idea of how much an electrician will charge for labor.
Requirements for Circuit Breakers and Cables
Water heaters typically draw a maximum current of 30 amps at 240 volts, requiring a minimum 10-gauge wire size according to the electric code. A conventional electric water heater does not require equipment that runs on 120-volt power, so the cable supplying it needs only two conducting wires and a ground wire. The conductors are black and red, with the ground wire being bare. These wires are bundled in the sheathing of a roll of 10/2 NM-B cable.
An appliance that runs on 240-volt power must be controlled by a dedicated double-pole breaker, consisting of two breakers joined together and occupying two adjacent slots in the electrical panel. If you are installing an electric water heater for the first time, ensure that your panel has room for a 30-amp double-pole breaker. Otherwise, you must eliminate one or two circuits or upgrade the panel.
The Basic Wiring Procedure
The cable supplying power to a water heater must be enclosed in a metallic conduit and attached to a plate on the main wiring terminal on the top of the water heater. If you are replacing an existing water heater, remove the plate to access the wiring. When installing an electric water heater for the first time, feed the cable through the conduit and knock-out hole in the cover before attaching the conduit to the cover. All of this must be done with the circuit breaker off.
To connect wiring to a new water heater, an electrician will first check the wires with a multimeter to ensure there is no voltage. Next, they will twist the black circuit wire to the black wire in the water heater terminal, twist the red ones together in the same way, and screw wire caps onto each wire splice. Then, the electrician wraps the ground wire around the ground screw in the terminal, tightens the screw, and replaces the cover.
Wiring Tankless and Hybrid Water Heaters
The procedure for wiring a tankless water heater is essentially the same as wiring one with a tank. The only difference is that the wiring terminal is usually on the bottom or side of the unit, not the top. Always check the current draw of the unit (displayed on a label) to ensure you purchase a circuit breaker with the proper current rating.
A hybrid water heater utilizes two methods to heat water. It employs a 120-volt compressor, similar to that of a refrigerator, to maintain the water temperature, and a 240-volt heating element to quickly heat water when there is high demand. Due to the 120-volt compressor, the device has a neutral wire to divide the 240-volt voltage in half. As a result, a 10/3 cable, which includes a white neutral conductor, is necessary to supply power to the unit. There is an additional wire connection in the terminal, which is typically located on the side of the unit, and the neutral wire must be connected to the neutral bus in the panel.
Some ultra-efficient modern heat-pump water heaters do not have a resistive heating element and do not require 240-volt power. Connecting one of these to a 120-volt, 15-amp circuit may be as simple as plugging it in. When hardwiring, the process is similar to wiring an outlet: connect the black wires, connect the white wires, attach wire caps, connect the ground wire to the ground screw on the unit, and you’re done.
FAQ
1. Can I wire an electric water heater myself?
Yes, it is possible to wire an electric water heater yourself if you have experience with electrical work and feel confident in your abilities. However, it is important to note that working with electricity can be dangerous, so it is recommended to hire a licensed electrician if you are unsure or uncomfortable with the task.
2. What tools do I need to wire an electric water heater?
You will need a few basic tools to wire an electric water heater, including wire cutters, wire strippers, a voltage tester, a screwdriver set, and electrical tape. It is also important to have the appropriate gauge of electrical wire and the necessary connectors for your specific water heater model.
3. How do I determine the correct wire size for my electric water heater?
The correct wire size for your electric water heater depends on the amperage of the heater and the distance between the heater and the electrical panel. You can refer to the manufacturer’s specifications or consult with a licensed electrician to ensure you are using the correct wire size for your specific installation.
4. What is the proper way to connect the wires to the water heater?
Before connecting the wires to the water heater, make sure the power is turned off at the electrical panel. Then, strip the insulation from the wires, making sure to leave enough exposed wire to make a secure connection. Connect the black wire to the black or hot terminal, the white wire to the white or neutral terminal, and the green or bare copper wire to the green or ground terminal. Secure the connections with wire connectors and cover them with electrical tape.
5. Are there any safety precautions I should take when wiring an electric water heater?
Yes, there are several safety precautions to keep in mind when wiring an electric water heater. Always turn off the power at the electrical panel before working on the water heater. Use a voltage tester to ensure the power is off before touching any wires. Make sure all connections are secure and free from any exposed wires or loose connections. Finally, double-check your work and have it inspected by a professional if you are unsure.
6. Can I use a standard electrical outlet for my electric water heater?
No, electric water heaters require a dedicated circuit and should not be plugged into a standard electrical outlet. They typically require a higher voltage and amperage than a standard outlet can provide. It is important to have a licensed electrician install the appropriate circuit and outlet for your specific water heater.
7. How often should I check the wiring on my electric water heater?
It is recommended to check the wiring on your electric water heater at least once a year to ensure there are no loose connections or signs of damage. Additionally, if you notice any changes in the performance of your water heater or experience any electrical issues, it is important to have the wiring inspected by a licensed electrician as soon as possible.